Apparatus and method for introducing additives to fibrous products

Abstract

A method and apparatus for expanding the fiber column produced by a rotary fiber manufacturing unit and intermingling additive particles with the fibers. A rotating bell-shaped shell is mounted beneath the rotary disc of the manufacturing unit so that the lower portion of the shell is in the path of the fiber column, causing the column to be outwardly deflected. Additive particles are introduced from within or beneath the shell and are radially directed into the fiber column. Liquid binder may be introduced to the fibers and water may be directed onto the inner surface of the shell to cool the shell to prevent curing of binder coming in contact with the shell. The fibers may be glass fibers and the particles may be foamed resin, fibers or particles of various types.

What is claimed is: 
     
       1. In apparatus for manufacturing fibers by a rotary process, wherein molten material capable of being fiberized is delivered to a disc connected to an axially extending hollow shaft for rotation therewith, the disc having a sidewall containing a plurality of fiberizing openings and the apparatus including means for impacting fibers extruded from the holes with a gaseous stream to form a column of downwardly moving fibers, the improvement comprising: a shell in the shape of a body of revolution mounted beneath the disc for rotation therewith;   the shell having an upper portion, a lower portion, an outer surface and an inner surface;   the lower portion of the shell having a greater diameter than the upper portion and being positioned in the path of movement of the fiber column whereby the fiber column is expanded radially outwardly; and   a conduit extending through the hollow shaft for introducing particles of additive material to the fiber column to substantially uniformly intermingle the additive particles with the fibers of the column, said conduit terminating within the confines of the shell.   
     
     
       2. The improvement of claim 1, including a bottom plate and means connecting the bottom plate to the shell so as to provide openings adjacent the bottom plate and the shell through which particles of additive material may flow. 
     
     
       3. The improvement of claim 2, including a second conduit extending through the hollow shaft, the second conduit extending through an opening in the bottom plate and terminating beneath the bottom plate, whereby particles of additive material different from additive material introduced through the first-mentioned conduit may be introduced. 
     
     
       4. The improvement of claim 2, wherein the openings adjacent the connection between the bottom plate and the shell comprise spaces between the shell and the bottom plate. 
     
     
       5. The improvement of claim 4, wherein the spaces between the shell and the bottom plate are formed by a circumferential edge portion on the bottom plate spaced from and substantially parallel to the adjacent lower portion of the shell, the connection between the bottom plate and the shell being at spaced points along the circumferential edge portion of the plate. 
     
     
       6. In a process for manufacturing fibers whereby molten material capable of being fiberized is delivered to a rotating disc connected to a rotating axially extending hollow shaft, the disc having a sidewall containing a plurality of openings through which fibers are extruded, the process including the step of impacting fibers extruded from the holes with a gaseous stream to form a column of downwardly moving fibers, the improvement comprising: providing a shell in the shape of a body of revolution beneath the disc, the shell having an upper portion, a lower portion, an outer surface and an inner surface, the lower portion of the shell having a greater diameter than the upper portion;   positioning the shell beneath the disc so that the lower portion of the shell is in the path of movement of the fiber column and rotating the shell to expand the fiber column radially outwardly; and   introducing particles of additive material through the hollow shaft into the confines of the shell, the centrifugal force of the rotating shell causing the particles to be distributed radially outwardly of the shell to substantially uniformly intermingle the additive particles with the fibers in the column.   
     
     
       7. The improvement of claim 6, including the step of radially outwardly introducing particles of a different additive material at a point beneath the rotating shell. 
     
     
       8. In apparatus for manufacturing fibers by a rotary process, wherein molten material capable of being fiberized is delivered to a disc connected to an axially extending hollow shaft for rotation therewith, the disc having a sidewall containing a plurality of fiberizing openings and the apparatus including means for impacting fibers extruded from the holes with a gaseous stream to form a column of downwardly moving fibers, the improvement comprising: a shell in the shape of a body of revolution mounted beneath the disc for rotation therewith;   the shell having an upper portion, a lower portion, an outer surface and an inner surface;   the lower portion of the shell having a greater diameter than the upper portion and being positioned in the path of movement of the fiber column whereby the fiber column is expanded radially outwardly; and   a conduit extending through the hollow shaft for introducing particles of additive material to the fiber column to substantially uniformly intermingle the additive particles with the fibers of the column, said conduit terminating beneath the confines of the shell.   
     
     
       9. The improvement of claim 8, including means for directing water against the inner surface of the shell to cool the shell and means for introducing liquid binder to the fiber column, the means for introducing liquid binder to the fiber column comprising means for directing a stream of liquid binder against the inner surface of the shell beneath the point at which water is introduced. 
     
     
       10. The improvement of claim 9, wherein the means for introducing liquid binder to the fiber column comprises means for radially outwardly directing a spray of liquid binder toward the fiber column from a point beneath the shell, said means comprising a nozzle connected to a conduit extending through the hollow shaft, the nozzle being located beneath the conduit through which the particles are introduced. 
     
     
       11. In a process for manufacturing fibers whereby molten material capable of being fiberized is delivered to a rotating disc connected to a rotating axially extending hollow shaft, the disc having a sidewall containing a plurality of openings through which fibers are extruded, the process including the step of impacting fibers extruded from the holes with a gaseous stream to form a column of downwardly moving fibers, the improvement comprising: providing a shell in the shape of a body of revolution beneath the disc, the shell having an upper portion, a lower portion, an outer surface and an inner surface, the lower portion of the shell having a greater diameter than the upper portion;   positioning the shell beneath the disc so that the lower portion of the shell is in the path of movement of the fiber column and rotating the shell to expand the fiber column radially outwardly; and   moving particles of additive material through the hollow shaft to a point beneath the rotating shell and radially outwardly introducing the particles to the fibers in the column to substantially uniformly intermingle the additive particles with the fibers in the column.   
     
     
       12. The improvement of claim 11, including the steps of directing water against the inner surface of the shell to cool the shell and introducing liquid binder to the fiber column by directing a stream of liquid binder against the inner surface of the shell beneath the point at which water is introduced. 
     
     
       13. The improvement of claim 12, wherein the step of introducing liquid binder to the fiber column comprises radially outwardly directing a spray of liquid binder toward the fiber column from a point beneath the shell beneath the point at which additive particles are introduced.